1. Field of the Invention
The present invention relates to network technology and more particularly, to an impedance matching device-integrated network signal processing circuit, which has a microstrip coil of an impedance matching device connected in series to each circuit path thereof to keep input impedance and output impedance in balance, achieving the purpose of network signal transmission stability.
2. Description of the Related Art
With fast development of computer technology, desk computers and notebook computers are well developed and widely used in different fields for different applications. It is the market trend to provide computers having high operating speed and small size. Further, network communication technology brings people closer together, helping people to gather information about living, learning, working and recreational activities. By means of network communication, people can communicate with one another to send real time information, advertising propaganda or e-mail. Further, through the Internet, people can search information, send instant messages, or play on-line video games. The development of computer technology makes the relationship between people and network unshakable and inseparable. Network information can spread far and wide without restrictions on time, place or space. Further, through the Internet, people can upload, download, back up all the necessary information for daily life, work, study or consultation. A variety of network platforms are available for shopping, information sharing, and exchange of experiences. Internet applications are now more powerful than ever. Men or women are fond of social networking applications.
In a network, cable or wireless interference means may be selectively used for data transmission. The technology of cable connection for network application needs to use network connectors. With the development of network applications, the data transmission capacity is greatly increased. In order to satisfy users demands, network connection speed has been greatly improved from the rate of 10 Mbps up to 100 Mbps or 1 Gbps. The advanced fiber optic network speed can support 10 Gbps. Further, computer networks are categorized by their scope or scale. The usually said categories of networks are LAN (local area network), MAN (metropolitan area network), WAN (wide area network). The most well-known WAN is the Internet. When linking a network signal, or uploading or downloading network data, the network signal is transmitted from a network signal cable through a network connector to a motherboard in a computer. During the transmission of the network signal, an impedance mismatch occurs between the motherboard of the computer and the network cable (for example, the impedance at the network connector is about 100Ω; the impedance at the motherboard of the computer is about 85Ω), resulting in signal interference, network signal transmission instability or interruption of signal. According to the conventional design, as shown in FIG. 7, the motherboard A of the computer is connected to the network cable B1 through the network connector B so that the motherboard A can get network signals, however, the impedance mismatch between the motherboard A (85Ω) and the network cable B1 (100Ω) must be balanced. According to this prior art design, transformer modules B21 of a processing circuit B2 of the network connector B are adapted for impedance matching, however, these transformer modules B21 cannot keep the impedance of the motherboard A in fully balance with the impedance of the network cable B1, causing network signal transmission instability, interference or signal interruption. The transformer modules B21 of the network connector B are made by manually winding coils round respective magnetic cores, where the number of turns in the coils determines the application function of the transformer modules B21. However, manually winging the coils round the respective magnetic cores tend to cause overlapped or staggered coils. Further, it is difficult to accurately control the number of turns in the coils of the transformer modules and their dimensions. In actual application, the functioning of the transformer modules can be unstable.
Therefore, it is desirable to provide a network processing circuit that eliminates the aforesaid problems and that effectively achieves impedance matching to keep the impedance of the network cable in balance with the impedance of the motherboard of the computer, so as to avoid network signal transmission interference and to assure network signal transmission stability.